1. Field of the Invention
This invention relates generally to fasteners and more particularly to a fastener constructions which provide redundant load paths for fail-safe operation.
2. Description of the Prior Art
There has long been a need for a fastener of simplified construction which would continue to operate in the event of a failure of a constituent part. This need has been intensified by the space program in the course of which components are being designed which must be joined in space without the conveniences available on earth. For example, in the space environment, it is not easy, and is sometimes impossible, to remove and replace a failed fastener. Additionally, such tasks are intended to be performed primarily by robots which lack the ability of human beings to readily detect a failure and react in a proper fashion to assess the situation and determine a course of action.
Known to the prior art, for example, are lock nut assemblies of the nature disclosed in U.S. Pat. Nos. 4,889,458 to Taylor and No. 4,840,529 to Phillips. These utilize coaxial fastening members which are threadedly engageable. A similar construction disclosed in U.S. Pat. No. 4,863,329 to Wilson has been utilized for resiliently component so as to isolate the component from vibration. Another similar known construction, as disclosed in U.S. Pat. No. 4,925,364 to Das, provides an adjustable spacer for maintaining a minimum of separation between two translating members as, for example, in a gas turbine engine.
However, none of these constructions, although generally of a coaxial design, provide dual load paths in the event of a failure of one of the coaxial elements. It was with knowledge of the prior art and the limitations existing in such prior art devices that the present invention has been conceived and is now reduced to practice.